1. Field of the Invention
This invention relates generally to dispensing closures that are secured to a container to discharge the contents thereof, and more particularly to a tamper evident seal that indicates that someone has attempted to gain access to the contents of the container. The same seal, one breached, functions as a proof of purchase tab.
2. Prior Art
Dispensing closures, comprising a closure body that is screwed, or otherwise secured, to the neck of a container, and a spout that is mounted within a cavity in the upper surface of the closure body for pivotal movement, are well known. A discharge opening is defined through the closure body, and a bore extends longitudinally through the spout. The spout has an enlarged, cylindrical base, and trunnions are formed on opposite sides of the base. The trunnions fit into grooves in the walls defining the cavity in the closure body, so that the spout may be pivoted between a normal horizontal orientation, and a vertical orientation.
In the horizontal orientation, the cylindrical base of the spout blocks the discharge opening, and seals the contents of the container. In the vertical orientation, the bore in the spout is aligned with the discharge opening, and the contents of the container may be discharged through the spout. The container may be formed of a plastic that is resilient enough to be squeezed to discharge the contents thereof, or the container may be formed of a rigid plastic or glass, so that the contents may only be discharged when the container is inverted.
Such dispensing closures may be used to dispense food products such as margarine, cooking oils, catsup, mustard, etc. However, the dispensing closures are also suitable for lotions, medicines, such as salves or ointments, and numerous other applications.
The assignee of the instant application, Polytop Corporation of Slatersville, R.I., holds several patents that disclose, in detail, dispensing closures using pivotal spouts to discharge the contents of the container to which the closure is secured. Representative patents are Hazard U.S. Pat. Nos. 3,655,099; Hazard U.S. Pat. No. 3,655,103; Hazard et al U.S. Pat. No. 3,718,238; and Hazard et al U.S. Pat. No. 3,957,181.
However, when known dispensing closures have been used for dispensing food products, or salves or ointments, concern has arisen about maintaining the sanitary condition of the product being dispensed. In order to insure the ultimate consumer that the product has not been tampered with, or exposed to ambient conditions, and that sanitary standards have been met and maintained, demands have been made for tamper evident seals. Such seals, must be low in cost, easy to apply, and compatible with existing packaging machinery and techniques.
One such seal is disclosed in U.S. Pat. No. 4,081,108, granted Mar. 28, 1978 to Woodrow S. Wilson and Robert E. Hazard and assigned to Polytop Corp. The Wilson et al patent provides a tamper evident seal that assumes the form of a relatively flexible strap (16) which connects the movable end of a spout (14) with the cap body (18) employed in such closure. The use of such a strap makes it possible to mold the spout and the cap as a unitary article (as shown in FIG. 3). The strap is shaped and dimensioned to facilitate location of the spout during assembly of the spout on the cap, or cap body, and if desired, functions as a cover for the bore (38) in the spout when the spout is assembled to the closure body, by inserting trunnions (42) into bearing slots (30, 32) in the closure body.
Another approach for providing a tamper evident seal for a dispensing closure is disclosed in U.S. Pat. No. 4,763,801, granted Aug. 16, 1988 to Joseph D. Nycz, and assigned to Owens-Illinois Closure Inc. Such patent discloses a dispensing closure (14) which is secured to the finish of a container. The closure includes a molded plastic body (20) with an irregular, generally horizontal top structure and a dispensing opening (50) in such top structure. A pivotable spout (22) is frictionally and pivotally attached to the top structure, and can be pivoted between a generally horizontal, closed position, and an upright, open position wherein the bore in the spout is aligned with the dispensing opening (as shown in FIG. 7). The closure further includes a dispensing control member (disc 24) which is rotatable in a horizontal plane with respect to the body portion, the disc having a slot (74) defined therein. The disc is capable of rotation to bring the slot into alignment with the pivotable spout, to permit the pivotable member to be pivoted through the slot from the closing position (FIGS. 4-5) to the open, or dispensing portion (FIG. 7). As the pivotable member is swung into its open position for the first time, bridge member (76) is severed, thus providing a visible indication to the consumer, or store employee, that someone has attempted to gain access to the contents of the container.
Several other tamper evident seals, of different constructions, have been developed in recent years. For example, see the removable flange (70) in U.S. Pat. No. 4,595,123, granted to S. M. Libit, that is secured to the top of a dispensing closure, in the vicinity of hinged cap (22) by depending bosses 81. The indicia formed in the container top, underlying the flange, is made visible by removal of the flange (as shown in FIGS. 7 & 9).
Additional tamper-indicating seals for plastic closures are shown in Shastal U.S. Pat. No. 4,775,065; Kitterman U.S. Pat. No. 4,941,592; Gross U.S. Pat. No. 5,123,561; and Gross U.S. Pat. No. 5,201,440.
While several of the patented closures cited above disclose tamper evident seals that have met with varying degrees of consumer acceptance, no known seal for dispensing closure has been devised to provide an effective, tamper evident seal and a proof of purchase indicator. Furthermore, no known seal has been devised that combines both of these qualities, into a simple, aesthetically pleasing, molding that is compatible with existing packaging equipment, and can be mass-produced at a minimum cost, per unit. Furthermore, such dual purpose seal must be strong enough to preclude unwarranted opening of the spout during shipment, yet weak enough to yield readily, and break away clearly from the spout, when the user attempts to open the spout for the first time.